I'm 15, never had sex. I found quite a large, painless white pimple on the shaft of my penis. I didn't intentionally pop it, it popped after I tried to stretch the skin to look at it (my penis was semi-erect, it may have stretched the size of the pimple causing it to pop)I have very recently been to China Once it popped some white, greasy puss came out followed by a small amount of blood. Now it is just a red mound. There was only one, and it was painless when I popped it and painless afterwords.